Covert routing may be used in attempts to infiltrate network computer systems and circumvent access control policies. Further, through covert routing users, or devices may gain access to restricted computer systems. Covert routing may be facilitated by secret cooperation between the users or the devices and a covert router. The covert router may receive packet data transmissions that are addressed to an unrestricted computer system and may redirect the packet data transmissions of the infiltrating users or devices to restricted computer systems. In certain circumstances, it may be difficult to detect the occurrence of covert routing or prevent the covert routing. Further, it may be difficult to identify network routers or users that participate in malicious activity. For example, packet data transmissions in a network may be inaccessible for monitoring due at least in part to legal or contractual requirements or because the packet data transmissions may be encrypted.
Accordingly, it may be challenging to detect the occurrence of covert routing activity or parties that participate in covert routing. Further, it may also be challenging to distinguish covert routing activity from non-malicious activity.